Individuals with traumatic brain injury (TBI) aim to improve their physical and cognitive abilities in order to function more independently in the community. The past research emphasis in TBI has been on neuropsychologic functioning with little attention paid to improving physical work capacity and its role in improving overall health and quality of life. It is well known from other patient populations that physical function and improvements in overall physical fitness can have positive influences on the psychological and emotional well-being of the individual. This proposal plans to investigate an experimental rehabilitation intervention referred to as body weight support treadmill training (BWSTT) and has shown promise in patients with stroke and spinal cord injury. Its effects have not been formally characterized in individuals with TBI. It is a therapy that requires a large investment in equipment and personnel, thus its utility demands full characterization. The proposed studies will be performed in a post acute residential treatment center in patients who are non-ambulatory or require maximal to moderate assistance to walk. Patients will be randomly assigned to a BWSTT group or traditional physical therapy (control) group. The goal of specific aim 1 is to assess the effects of (BWSTT) on overground walking speed, balance and muscle force production. The goal of specific aim 2 is to assess the effects of BWSTT on neuropsychologic function. Neuropsychologic outcomes to be measured are attention, memory, and emotional status. Disability, handicap, and quality of life will also be assessed. In addition, specific aim 2 will also examine the acute changes in memory, attention and psychomotor speed that may occur as a result of the more intense ambulation training (BWSTT vs. control). Preliminary results show significant improvements in clinical tests of balance and immediately following these high intensity sessions improvements in selective attention have been demonstrated. For both specific aims, 30-35 patients in each group will have baseline assessments upon admission to the center and after 4, 8, and 12 weeks of treatment and 6 months post discharge. If successful this project will form the basis for longitudinal studies of people living with TBI and the impact of improved locomotion and physical work capacity on neuropsychologic function, quality of life and secondary disease prevention. The latter is of particular importance from a public health perspective since the individual with TBI is usually young and will endure the permanent disabling effects of TBI for many years.